Introduction: During the In'uenza A(H1N1)v outbreak of 2009-2010 a study was set up to
collect information on contact behaviour during ill and healthy condition. The aim of the study
was to investigate whether contact patterns di'er when participants were feeling ill or not.
Methodology: Estimation of the contact rate matrices involved a weighted average approach for
a dataset considering full contact information and for a dataset consisting of the contacts capped
at 33 as well as estimation based on a censored negative binomial likelihood. The comparison
is based on 3 measures: the ratio of R0's, the Euclidean distance between normalised leading
eigenvectors of the next generation matrix and the sum of the absolute di'erences.
Results: Studying the participants with contact information during ill and healthy condition
(140) and the comparison of ill participants (283) to POLYMOD UK participants (1012) showed
signi'cant di'erences between contact patterns. Where a reducti